Sheet and/or web materials are widely used in many types of products such as, for example, personal care products, garments, medical fabrics and the like. Some sheets or webs made from certain inexpensive raw materials could have an even wider range of applications in these products if the sheets or webs could be designed to have enhanced properties or attributes.
For example, polyolefins are widely used in the manufacture of sheet or web materials. Polyolefin sheets or webs tend to be hydrophobic and relatively inert. In the past, topical or internal additives have been used with polyolefin fibers to impart desired functional characteristics to fibrous webs. For example, liquid coatings have been applied to sheets and/or webs. These coatings and internal additives have limits to the types of functional characteristics that can be economically imparted to sheets or webs.
Particulates (e.g., finely divided solid materials and/or short fibers) may be physically mixed with fibrous material to impart some desired characteristics to sheets or webs. The finely divided solids tend to form "clumps" within the "carrier" material (e.g., the sheet or web). It can be difficult to bond or otherwise securely fix finely divided solids in the unevenly distributed clumps to the carrier material. The clumps are often held in place by physical entrapment or entanglement and may disintegrate or release much solid materials if sufficiently disturbed. Bonding with heat or adhesives tends to fix only the clumps and may also fail to secure finely divided solids within the clumps.
Some materials such as, for example, some sandpapers and/or some flocked materials can be manufactured by grossly attaching particulates to a charged substrate. These materials can be characterized by a relatively thick layer of particulates joined to an adhesive which covers the exterior of a substrate. Such materials and processes are not directed to securing a relatively uniform distribution of particulates (e.g., finely divided solid materials and/or short fibers) to individual exposed surfaces (e.g., individual fiber surfaces) of relatively permeable sheets and/or webs.
Thus, there is a need for a practical process for securing a relatively uniform distribution of particulates (e.g., finely divided solid materials and/or short fibers) to individual exposed surfaces of sheets and/or webs (e.g., relatively permeable materials) by substantially non-transient bonding. There is also a need for a practical continuous process suitable for high-speed manufacturing processes that secures a relatively uniform distribution of particulates (e.g., finely divided solid materials and/or short fibers) to individual exposed surfaces of sheets and/or webs (e.g., relatively permeable materials) by substantially non-transient bonding.
Furthermore, there is a need for fibrous composite structure composed of a matrix of fibrous material having individual exposed surfaces substantially throughout the matrix and a relatively uniform distribution of particulate material attached to at least a portion of the individual exposed surfaces of the fibrous material by substantially non-transient bonding. There is also a need for a film-like composite structure composed of a apertured film-like material having individual exposed surfaces and a relatively uniform distribution of particulate material attached to at least a portion of the individual exposed surfaces of the apertures film-like material by substantially non-transient bonding.